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      <img src="../logo.svg" class="logo" alt=""><h1>Check lat lon coordinates to see if each is approx. in general area of US Island Areas Guam, USVI, Amer Samoa or N Marianas</h1>
      <small class="dont-index">Source: <a href="https://github.com/USEPA/EJAM/blob/HEAD/R/latlon_is.valid.R" class="external-link"><code>R/latlon_is.valid.R</code></a></small>
      <div class="d-none name"><code>latlon_is.islandareas.Rd</code></div>
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    <div class="ref-description section level2">
    <p>See <a href="islandareas.html">islandareas</a></p>
    </div>

    <div class="section level2">
    <h2 id="ref-usage">Usage<a class="anchor" aria-label="anchor" href="#ref-usage"></a></h2>
    <div class="sourceCode"><pre class="sourceCode r"><code><span><span class="fu">latlon_is.islandareas</span><span class="op">(</span><span class="va">lat</span>, <span class="va">lon</span>, exact_but_slow_islandareas <span class="op">=</span> <span class="cn">FALSE</span><span class="op">)</span></span></code></pre></div>
    </div>

    <div class="section level2">
    <h2 id="arguments">Arguments<a class="anchor" aria-label="anchor" href="#arguments"></a></h2>


<dl><dt id="arg-lat">lat<a class="anchor" aria-label="anchor" href="#arg-lat"></a></dt>
<dd><p>vector of latitudes</p></dd>


<dt id="arg-lon">lon<a class="anchor" aria-label="anchor" href="#arg-lon"></a></dt>
<dd><p>vector of longitudes</p></dd>


<dt id="arg-exact-but-slow-islandareas">exact_but_slow_islandareas<a class="anchor" aria-label="anchor" href="#arg-exact-but-slow-islandareas"></a></dt>
<dd><p>optional logical, set it to TRUE to check each point vs
boundaries in <a href="states_shapefile.html">states_shapefile</a> to identify which ones are in Island Areas according to that shapefile.
The default method here is much faster, but just checks if a point is within a bounding box
that should approximate each of the Island Areas, found in the object <a href="islandareas.html">islandareas</a>.</p></dd>

</dl></div>
    <div class="section level2">
    <h2 id="value">Value<a class="anchor" aria-label="anchor" href="#value"></a></h2>
    <p>vector of TRUE / FALSE values indicating a given lat lon pair
is approximately in one of the rough bounding boxes that includes the 4 Island Areas.</p>
    </div>
    <div class="section level2">
    <h2 id="see-also">See also<a class="anchor" aria-label="anchor" href="#see-also"></a></h2>
    <div class="dont-index"><p><code><a href="latlon_is.usa.html">latlon_is.usa()</a></code> <code>latlon_is.islandareas()</code> <code><a href="latlon_is.available.html">latlon_is.available()</a></code> <code><a href="latlon_is.possible.html">latlon_is.possible()</a></code></p></div>
    </div>

    <div class="section level2">
    <h2 id="ref-examples">Examples<a class="anchor" aria-label="anchor" href="#ref-examples"></a></h2>
    <div class="sourceCode"><pre class="sourceCode r"><code><span><span class="kw">if</span> <span class="op">(</span><span class="cn">FALSE</span><span class="op">)</span> <span class="op">{</span> <span class="co"># \dontrun{</span></span>
<span><span class="co"># this would require the testpoints_1000 data from the EJAM package:</span></span>
<span>  <span class="va">isles</span> <span class="op">&lt;-</span> <span class="fu"><a href="https://rdrr.io/r/base/which.html" class="external-link">which</a></span><span class="op">(</span><span class="fu">latlon_is.islandareas</span><span class="op">(</span>lat <span class="op">=</span> <span class="va">testpoints_1000</span><span class="op">$</span><span class="va">lat</span>, lon <span class="op">=</span> <span class="va">testpoints_1000</span><span class="op">$</span><span class="va">lon</span><span class="op">)</span><span class="op">)</span></span>
<span>  <span class="fu"><a href="mapfast.html">mapfast</a></span><span class="op">(</span><span class="va">testpoints_1000</span><span class="op">[</span><span class="va">isles</span>, <span class="op">]</span><span class="op">)</span> <span class="co"># c(213,785)</span></span>
<span>  <span class="fu"><a href="https://rdrr.io/r/base/which.html" class="external-link">which</a></span><span class="op">(</span><span class="op">!</span><span class="op">(</span><span class="fu"><a href="latlon_is.usa.html">latlon_is.usa</a></span><span class="op">(</span>lat <span class="op">=</span> <span class="va">testpoints_1000</span><span class="op">$</span><span class="va">lat</span>, lon <span class="op">=</span> <span class="va">testpoints_1000</span><span class="op">$</span><span class="va">lon</span><span class="op">)</span><span class="op">)</span><span class="op">)</span></span>
<span><span class="op">}</span> <span class="co"># }</span></span>
<span></span></code></pre></div>
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